Murphy, 25, was unveiled as Chris Judd's replacement at a press conference at Visy Park on Wednesday morning.
The brilliant midfielder was preferred over more experienced candidates Andrew Carrazzo, 29, and Kade Simpson, 28 – both of whom have been named joint vice-captains.
Blues coach Mick Malthousesaid the decision to appoint Murphy, after what he termed "an exhaustive process", was simply based on who was deemed the best person to "uphold the tradition and spirit of Carlton".
Malthouse said any of the five members of the leadership group would have been worthy of the position, but that Murphy was "the best man for the job".
"This isn't about who the best player is; it's about who the best leader is," he said.
"Marc's a young man who is a talent but we also know that he's very well admired and respected within the organisation."
Carlton president Stephen Kernahan, one of the club's greatest skippers, said Murphy was taking the role at the perfect time in his career.
Murphy, a member of the Blues' leadership group for six years, said he was humbled and excited by the "massive honour". He admitted he had "big shoes to fill" and was lucky he still had Judd to call on for guidance.
The 142-gamer, who described himself as "a very competitive person", believes he will "grow into the job" and is determined to create his own legacy.
"It's been a massive aspiration to one day captain the club," he said. "I'm not one of the most vocal blokes at the club but I think I lead by example and give 100 per cent week-in, week-out."
Thanks for everyone's messages. I'm very excited and humbled to be appointed captain of such a great club
— Marc Murphy (@marcmurphy3) March 13, 2013
The No.1 pick in the 2005 AFL Draft, Murphy has blossomed into one of the AFL's best midfielders, averaging 26.3 disposals and almost a goal a game over the past five seasons.
In 2011 he won the AFL Coaches' Association Award, All Australian selection and the Blues' best and fairest (after finishing second, second and third in the previous three seasons).
Last year he missed six games with a shoulder injury, but still came fifth in the club award. Perhaps significantly, he also captained his team for four games during Judd's suspension for a 'chicken wing' tackle.
Murphy and his father John, who won six best and fairests with Fitzroy and South Melbourne and captained the Lions, become just the seventh father-son combination to be appointed captains of AFL/VFL clubs. This exclusive club includes some illustrious names – the Watsons (Tim and Jobe), Abletts (Gary snr and Gary jnr), Nashes (Bob and Laurie) and Pannams (Charlie snr, Charlie jnr and Alby).
Listen to AFL.com.au writers Ashley Browne and Howard Kotton discuss the Blues' choice of captain below.